Bathymetry, magnetic and shallow seismic data collected north and south off Visakhapatnam revealed the extension of onshore lineaments to offshore. Stability of the area has been studied from the physical properties of sediment samples, bathymetry, magnetic and seismic data, which are collected before and after Great Sumatra Eanhquake (GSE), followed by Tsunami. Detailed analysis of shipborne gravity and satellite gravity data around 12 degrees N latitude indicated isolated gravity lows away from the coast up to 85 degrees E Ridge gravity low. These gravity lows probably suggest transform rifted margin evolved during the breakup of India from Antarctica and particularly gravity low at 83 degrees E long are due to gradual rise of isolated high in the basement with hard sedimentary loading processes.